Development of standard sample for quantitative analysis of hydrogen by RBS/ERDA method with electrostatic accelerator

Determination of hydrogen content is an important evaluation for materials such as DLC and Amorphous carbon film, as their properties change with hydrogen concentration. Rutherford Back-scattering Spectroscopy (RBS) and Elastic Recoil Detection Analysis (ERDA) are effective methods of analyzing thin film samples, since they do not require standard samples. However, for improving the accuracy of analysis, standard samples with known H concentrations are eagerly anticipated but the analysis error mostly depends with the equipment condition and experience of the analyst. The objective of the study is to develop a thin film applicable as a standard sample for RBS/ERDA. As a material, vanadium oxide phthalocyanine (VO-Pc) having a known hydrogen amount and excellent chemical stability was selected. The thin film prepared inside the vacuum and material was evaporated on the Si substrate to from a thin film with VO-Pc powder. This film sample was evaluated for crystal structure by XRD, formed thin film was confirmed VO-Pc. Measurement accuracy for the RBS/ERDA was checked using the developed standard sample and it was founded to be 28±1% of H concentration. This is consistent with inherent stoichiometric composition of VO-Pc(27.6%-H). From this it was found that RBS/ERDA measurement currently is highly accurate. (author)